Technetium-99m labeled peptides for imaging comprising a single thiol moiety

Abstract

The invention elates to radiolabeled imaging of a mammalian body. The invention in particular provides for reagents labeled with technetium-99m for such imaging. The invention provides peptides which bind Tc-99m and which can be targeted to specific sites within a mammalian body.

What is claimed is: 
     
       1. A compound comprising: a) a peptide having between 4 and 100 amino acid residues; and   b) covalently linked to the peptide, a radioisotope complexing group comprising a single reduced thiol moiety that is:   A--CH(B)-- C(RR')!.sub.n --X     wherein     A is H or HOOC;   B is H, SH, or NHR", where R" is H or lower alkyl;   X is SH or NHR", where R" is H or lower alkyl;   R and R' are independently H or lower alkyl;   n is 0, 1 or 2; and   where B is NHR", X is SH and n is 1 or 2;   where X is NHR", B is SH and n is 1 or 2;   where B is H, A is HOOC, X is SH and n is 0 or 1;   wherein the compound is capable of imaging target sites within a mammalian body when labeled with technetium-99m.   
     
     
       2. The compound according to claim 1 wherein the peptide and the complexing group are covalently linked through one or more amino acids. 
     
     
       3. The compound according to claim 1 wherein the peptide is chemically synthesized in vitro. 
     
     
       4. The compound according to claim 3 wherein the peptide is synthesized by solid phase peptide synthesis. 
     
     
       5. The compound according to claim 3 wherein the complexing group is covalently linked to the peptide during in vitro chemical synthesis. 
     
     
       6. The compound according to claim 4 wherein the completing group is covalently linked to the peptide during solid phase peptide synthesis.